.\" -*- nroff -*-
.\" Copyright 2014 Cisco Systems, Inc.  All rights reserved.
.\" Copyright 2006-2008 Sun Microsystems, Inc.
.\" Copyright (c) 1996 Thinking Machines Corporation
.\" Copyright (c) 2020      Google, LLC. All rights reserved.
.\" $COPYRIGHT$
.TH MPI_Cart_get 3 "#OMPI_DATE#" "#PACKAGE_VERSION#" "#PACKAGE_NAME#"
.SH NAME
\fBMPI_Cart_get\fP \-  Retrieves Cartesian topology information associated with a communicator.

.SH SYNTAX
.ft R
.SH C Syntax
.nf
#include <mpi.h>
int MPI_Cart_get(MPI_Comm\fI comm\fP, int\fI maxdims\fP, int\fI dims\fP[], int\fI periods\fP[],
	int\fI coords\fP[])

.fi
.SH Fortran Syntax
.nf
USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_CART_GET(\fICOMM\fP, \fIMAXDIMS\fP, \fIDIMS\fP, \fIPERIODS\fP, \fICOORDS\fP, \fIIERROR\fP)
	INTEGER	\fICOMM\fP, \fIMAXDIMS\fP, \fIDIMS\fP(*), \fICOORDS\fP(*), \fIIERROR\fP
	LOGICAL	\fIPERIODS\fP(*)

.fi
.SH Fortran 2008 Syntax
.nf
USE mpi_f08
MPI_Cart_get(\fIcomm\fP, \fImaxdims\fP, \fIdims\fP, \fIperiods\fP, \fIcoords\fP, \fIierror\fP)
	TYPE(MPI_Comm), INTENT(IN) :: \fIcomm\fP
	INTEGER, INTENT(IN) :: \fImaxdims\fP
	INTEGER, INTENT(OUT) :: \fIdims(maxdims)\fP, \fIcoords(maxdims)\fP
	LOGICAL, INTENT(OUT) :: \fIperiods(maxdims)\fP
	INTEGER, OPTIONAL, INTENT(OUT) :: \fIierror\fP

.fi
.SH INPUT PARAMETERS
.ft R
.TP 1i
comm
Communicator with Cartesian structure (handle).
.TP 1i
maxdims
Length of vectors dims, periods, and coords in the calling program (integer).

.SH OUTPUT PARAMETERS
.ft R
.TP 1i
dims
Number of processes for each Cartesian dimension (array of integers).
.TP 1i
periods
Periodicity (true/false) for each Cartesian dimension (array of logicals).
.TP 1i
coords
Coordinates of calling process in Cartesian structure (array of integers).
.ft R
.TP 1i
IERROR
Fortran only: Error status (integer).

.SH DESCRIPTION
.ft R
The functions MPI_Cartdim_get and MPI_Cart_get return the Cartesian topology information that was associated with a communicator by MPI_Cart_create.

.SH ERRORS
Almost all MPI routines return an error value; C routines as the value of the function and Fortran routines in the last argument.
.sp
Before the error value is returned, the current MPI error handler is
called. By default, this error handler aborts the MPI job, except for I/O function errors. The error handler may be changed with MPI_Comm_set_errhandler; the predefined error handler MPI_ERRORS_RETURN may be used to cause error values to be returned. Note that MPI does not guarantee that an MPI program can continue past an error.

.SH SEE ALSO
.ft R
.sp
.nf
MPI_Cartdim_get
MPI_Cart_create
